In order to turn off the device hold down the Power key for a short while.Afterwards press and hold together: Volume Up + Home + Power button for a while.You can release held keys when the Samsung Logo appears on the screenThen select from Recovery Mode menu "wipe data / factory reset" using Volume buttons to navigate and Power button to confirm.Choose "Yes -- delete all user data" to confirm the whole operation.After that select option "reboot system now".Well done! The hard reset has just been performed.

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Start by turninng on the device by using the Power button.From the Home Screen go to Menu and then to Settings.Tap Privacy and then Factory data reset.In the next step find and choose Reset device.To confirm your choice select Erase everything.That's all. The hard reset is done